How to copy a cartridge game in 1983

Wow... That was easier than I thought! I always wanted one of those cartridge port expanders as a kid.

Thanks for the video!

Mucho smoke and mirrors for me!....thanks for sharing!

very cool

Very informative, thanks for sharing

When I was 15 years old in 1982, the local discount electronics chain Sun TV started selling the VIC-20 for $259. I lived about five miles from Sun TV, and rode my bicycle to the bank, withdrew the money, went to Sun TV, purchased the computer, and rode back home with the big clumsy box under my arm and across the handlebars. I learned a lot from that machine. Thanks for the memories!

Jim Butterfield: A proud Canadian!

Great video I have waited 30+ years to find this simple answer to how this was done. Way easier then I would have thought. I assume it's roughly the same process with the 64?

Very good my friend

Fascinating video! I had no idea that you could change where the RAM in a cartridge located itself. I would love to have a go at doing this just because, but I haven’t been able to find a slot expander as yet.

I've got the penultimate cartridge. I imagine I would still need a slot expander of some type to copy a cartridge?

Why won't the VIC just save the bytes from the cart straight away? Is that some part of the tape save code that refuses to? To save above $8000, couldn't you just copy the save routine from ROM, into RAM, patch it, and run it from there? Patch it so that whatever problem it has above 32K is no longer there. Presumably the machine itself can access memory above that address or else this wouldn't be a problem that ever comes up. So it's just a matter of read RAM, send some beeps to tape.

Or just copy the cart ROM to some RAM, which you had installed previously of course, 3K or even 8K not up to much. The machine has to be able to read cart ROM in order to run the games! And the piracy protection doesn't seem that sophisticated.

Did nobody do that? Did code in RAM run at constant speed? I mean, graphics wouldn't interrupt it at unpredictable times? The ZX Spectrum 16K model had that problem, only code in ROM or the upper 32K (in a 48K model) would run predictably, the first 16K RAM (from $4000 to $8000) was shared with the screen so accessing it would cause the CPU to pause if the screen wanted it first. It was OK though cos tape saving and loading code ran from ROM so the soft timing loops weren't affected. As long as it could get access to RAM eventually, before the next byte needed accessing, it was fine.

Excellent video, I've been looking for how to do this, thanks ;)

Interesting.
And weird: Why can the VIC load to block 5 from tape, but not save block 5 to tape? One might think it was supposed to be a bit of a copy protection, but then being able to save block 5 to floppy would not make sense ..

I have this ROM save/load program, which loads a game in just 15 seconds or so. It's really awesome. I wonder if anyone else knows about it? You first load the faster loader, then type SYS 4100 and then press the reset button. SYS 4103 saves a ROM.

I had a device for my 64 here in the UK that allowed me to copy commercial C64 tapes - you needed two datasettes - both connected to the device that plugged into the C64 cassette port - press play on one record on the other - perfect copy of the commercial software - no copy software required.

Great video, thanks for making it. I'm watching in 2025 for a refresher on how to do this as I have recently got a VIC cartridge that doesn't seem to be archived at all. And funny, I had totally forgot I did that little disassembly of ROMSAVE!

Also, it's really cool how those 8K RAM expanders are secretly so configurable! Funny how they're potentially more desirable than the 16K carts for that reason.